.gamma.-Butyrobetaine (actinine), from which the mammalian organism synthesises carnitine, was primarily characterised as a toxic substance which accelerates respiration, causes salivation and lacrimation, pupil dilation, vasoconstriction and heart stop in diastole (W. Linneweh, Z. Physiol. Chem., 42, 181, 1929). At the same time, in later papers other authors ascertained that .gamma.-butyrobetaine is extremely low toxic (LD.sub.50 &gt;7000 mg/kg, s.c.). (W. Rotzsch, I. Lorenz, E. Strack, Acta biol. med. ger. 1959,3,28-36).
In the literature data on nonsubstituted .gamma.-butyrobetaine cardiovascular effects are missing, though it was reported (Hosein E. A., McLennan H. Pharmacological action of .gamma.-butyrobetaine. Nature, 1959, 183, 328-329) that .gamma.-butyrobetaine is a substance similar to acetyl choline with a prolonged action. However, later the same authors reported that by an error the experiments involved, instead of .gamma.-butyrobetaine, its methyl ester which in fact possesses cholinergic properties. Contrary to the former nonesterified .gamma.-butyrobetaine was characterised as a pharmacologically inert substance (E. A. Hosein, P. Proulx, Isolation and probable functions of betaine esters in brain metabolism, Nature, 1960, 187, 321-322. A. S. V. Burgen, F. Hobiger. Brit. J. Pharmacol., 4, 229 (1949), E. Strack, K. Foesterling. Z. Physiol. Chem., 1953, 295, 377).
.gamma.-Butyrobetaine administration increases the level of carnitine biosynthesis in the organism serving as a substrate in this process. Thus, it would be natural to anticipate that in the organism at a simultaneous administration of camitine biosynthesis blocker 3-(2,2,2-trimethyl-hydrazinium)propionate and .gamma.-butyrobetaine, the pharmacological effect of 3-(2,2,2-trimethylhydrazinium)propionate should decrease because carnitine biosynthesis is activated if .gamma.-butyrobetaine concentration increases. On the contrary, it was now unexpectedly discovered that the opposite effect is observed, i.e. .gamma.-butyrobetaine intensifies the effect of 3-(2,2,2-trimethylhydrazinium)propionate on the cardiovascular system.